Previously, there have been attempts to provide a connector for a flexible hose with inlet and outlet fittings of heat exchangers. In a vehicle, it is advantageous to provide auxiliary heat exchangers such as a heater core to warm passenger compartment air, the engine cooling radiator, or an oil cooler for transmission oil of an automatic transmission. Typically, flexible hoses of elastomeric material have been utilized to transmit fluid from a using device such as an automatic transmission to an oil cooler located within the radiator tank of the radiator. The hose is connected to a heat exchanger inlet or outlet fitting by clamping its end portion around a cylindrical portion of the fitting utilizing various commercially available clamps. An example of a clamp presently available is a worm gear type device. Another means to attach flexible hoses to inlet and outlet fittings is to form a metal end fitting onto a hose during manufacture of the hose. The fitting is typically connected to the hose by means of a machine compression of the metal end fitting about the hose such as a swaging operation. The metal end fitting mates with a corresponding fitting on the heat exchanger and may be secured thereto by well known mechanical fastening and sealing means.
A major disadvantage of the aforementioned use of hose clamps to secure a hose to a fitting is the problem, particularly in an assembly plant, of having a separable hose and a clamp which can require an assembler to waste time in mating the hose and the clamp. Also, clamps require excessive assembly time and, thus, are costly. In addition, some locations of heat exchanger fittings are not easily reached by a tool to tighten a clamp. Thus, a clamp-type connection may be inappropriate or very inconvenient in some applications. The aforementioned use of preformed metal end fittings shares some of the same disadvantages as clamps and, in addition, are costly and require custom designed hose applications. Also, metal end fittings occupy a relatively large space and, thus, may be inappropriate in certain cramped applications. Also, metal fittings are not readily repairable and require considerable assembly time in forming a connection.
It is obvious from the aforementioned disadvantages of these other connector types, that a simple, composite and push-on connector is desirable. One example of a push-on connector is found in U.S. Pat. No. 4,163,573. This connector utilizes a housing with an aperture into which the hose is inserted and sealed by means of an O-ring which contacts the outer surface of the hose. The hose is axially secured by means of an annularly shaped hose gripping ring which is biased axially against an inclined ring by a coil spring. The coil spring pushes the gripping ring against an inclined surface of the other ring to bind against the hose. Unlike the present invention, the spring does not operatively engage the hose itself for retention.
The subject invention concerns a connector which is far simpler than the connector described above and utilizes a different sealing means for the flexible hose.
The sealing means is a fairly conventional and time-tested nipple-type fitting over which the hose end is extended. This type of connection has proven reliable in countless applications, both in and outside of the automobile industry. The subject application also discloses a cylindrical housing which encircles the nipple fitting in precise dimensional relation thereto. A coil-type wire spring is supported within the cylindrical recess of the housing. During assembly, the hose end is slid past an enlarged end bead of the nipple fitting and then engages the spring. Full insertion of the hose over the nipple fitting causes the spring to extend over the outer surface of the hose and, thus, be in tight spacing relation between the surrounding cylindrical housing and the hose's outer surface. The spring axially extends until the end is adjacent the radial enlargement of the hose caused by the nipple's enlarged bead. When in the aforedescribed configuration, reverse movement of the hose off of the fitting forces the end of the coil spring to tightly grip the hose which, by interference with the enlarged bead of the nipple, effectively prevents the hose from being readily removed from the connector except by very large forces.
Thus, the aforedescribed connector for flexible hoses provides a simple and reliable means of connecting the flexible hose to an inlet or outlet fitting of a heat exchanger. The nipple fitting, cylindrical housing and spring are secured in a composite assembly permitting the assembler to simply insert the plain end of a flexible hose over the enlarged beaded end of the nipple fitting and thereafter simply push the hose into the cylindrical housing to make the connection therebetween. Lastly, a simple rearward pull on the hose seats the hose end in the fitting causing the spring to tightly grip the hose adjacent the enlargement thereof caused by the enlarged nipple bead.
The aforesaid advantages and features of the subject connector for flexible hoses will be even more readily understood from a reading of the following Detailed Description of a Preferred Embodiment which is shown in the drawings as follows: